Could you please recommend a sufficiently elementary introduction to K3 gravitational instanton in general relativity and the problem of finding its explicit form?

Under 'sufficiently elementary' I mean the texts geared at physicists with basic knowledge of general realtivity but not much more than that (i.e. with almost no knowledge of modern differential geometry and algebraic geometry). To give a hint, I find the description of the problem in the book Solitons, Instantons and Twistors by Maciej Dunajski way too terse.

How are you supposed to have a basic knowledge of general relativity with no knowledge of differential geometry? How would you even talk about the metric tensor?
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Jonathan GleasonSep 8 '11 at 17:59

@Jonathan: the emphasis in my question was on modern differential geometry, i.e. I do know tensor calculus quite well but don't know much about bundles and other modern stuff.
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just-learningSep 8 '11 at 18:45

@Willie: thanks for the references, but at the first glance they appear to be a bit too technical.
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just-learningSep 8 '11 at 18:49